Modern flight deck displays for vehicles (such as aircraft or spacecraft) display a considerable amount of information, such as, vehicle position, speed, altitude, attitude, navigation, target, and terrain information. In the case of an aircraft, most modern displays additionally display a flight plan from different views, either a lateral view, a vertical view, or a perspective view, which can be displayed individually or simultaneously on the same display. Synthetic vision or simulated displays for aircraft applications are also being considered for certain scenarios, such as low visibility conditions. The primary perspective view used in synthetic vision systems emulates a forward-looking cockpit viewpoint. Such a view is intuitive and provides helpful visual information to the pilot and crew, especially during airport approaches and taxiing. In this regard, synthetic display systems for aircraft are beginning to employ realistic simulations of airports that include details such as runways, taxiways, buildings, etc. Moreover, many synthetic vision systems attempt to reproduce the real-world appearance of an airport field, including items such as light fixtures, taxiway signs, and runway signs. Flight deck display systems can be used to present taxi guidance information to the flight crew during taxi operations. For example, a synthetic flight deck display system can be used to show the desired taxi pathway to or from a terminal gate, along with a synthetic view of the airport.
Traditional aircraft taxi systems utilize the primary thrust engines (running at idle) and the braking system of the aircraft to regulate the speed of the aircraft during taxi. Such use of the primary thrust engines, however, is inefficient and wastes fuel. For this reason, electric taxi systems (i.e., traction drive systems that employ electric motors) have been developed for use with aircraft. Electric taxi systems can be more efficient than traditional engine-based taxi systems because they can be powered by an auxiliary power unit (APU) of the aircraft rather than the primary thrust engines. However, whether or not the use of electric drive to taxi is appropriate under a given set of conditions requires thought and judgment on the part of the pilot. Used inappropriately, electric taxi drive may be less effective and may even increase costs.
Accordingly, it is desirable to provide a system for use on an aircraft equipped with an electric drive taxi system that generates and displays an electric taxi index that assists a pilot in determining when to deploy electric taxi drive. Furthermore, other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.